We’re living in plague times, and everyone is suddenly super focused on their health. Cannabis smokers are especially nervous since it’s come to light that tobacco smokers who contract COVID-19 are more likely to develop more severe complications than non-tobacco smokers.
The World Health Organization says there are no peer-reviewed studies that analyze the effects of COVID-19 on tobacco smokers, but says that, “Smoking any kind of tobacco reduces lung capacity and increases the risk of many respiratory infections and can increase the severity of respiratory diseases. COVID-19 is an infectious disease that primarily attacks the lungs. Smoking impairs lung function making it harder for the body to fight off coronaviruses and other respiratory diseases.”
This definitely sounds like a warning to stay away from smoking marijuana. Both habits involve the inhalation of charred plant particulates and both produce tar. Inhaling burnt plant matter—which will always have carcinogens—is never a good thing. And at least two studies (one published in 2006 by the Robert Wood Johnson Foundation, the other in 2014 by the International Journal of Cancer) have found that smoking cannabis could even leave more tar in the lungs than tobacco. This is because cigarette smokers don’t generally hold the smoke in their lungs for as long as they can like cannabis smokers do.
But here's where it gets weird. The 2014 study we just mentioned—which found that cannabis smoke left tar in smokers’ lungs—also found no correlation between smoking cannabis and lung cancer.
“Results from our pooled analyses provide little evidence for an increased risk of lung cancer among habitual or long-term cannabis smokers, although the possibility of potential adverse effect for heavy consumption cannot be excluded,” wrote the authors.
Which makes you wonder: How do heavy cannabis smokers avoid the increased risk of lung cancer that cigarette smokers are affected by, despite having tar introduced into their system? So far no one really knows, but one possible answer can be found in a study from Complutense University of Madrid that found that THC was able to cause tumors to destroy themselves in animals. The research hasn't carried over to human trials.
A study conducted by the Federation of American Societies for Experimental Biology in 2011 found that CBD hampers cancer cell migration—meaning cancer cells are prevented from moving around and infecting other parts of the body.
But before you start dancing and proclaiming cannabis the cure for lung cancer, keep in mind that this research, while coming from respected agencies and being well-documented, is still only a very small amount of the work that needs to be done. It’s still up in the air until there's more peer review and repeatable results.
In the meantime another group concerned about how smoking cannabis can affect the lungs has been experimenting with the counterintuitive theory that the drug can treat asthma. People who suffer from asthma experience shortness of breath as a result of swelling in the airways. This swelling is caused by inflammation and can ultimately cause coughing, wheezing, shortness of breath and other symptoms.
And some patients claim that using cannabis actually helps relieve symptoms related to asthma (as strange as that may sound). So far there’s no scientific evidence to support the anecdotes, but it might not be so strange when you consider that cannabis has been shown to have anti-inflammatory and antispasmodic effects—meaning it could potentially treat the two worst symptoms of asthma. THC is also believed to suppress the immune system. Since asthma is an autoimmune disease, this effect could also be beneficial. A study published in Nature Partner Journals Primary Care Respiratory Medicine in 2016 also found that THC might have bronchodilatory properties, which means it could actually help to open the breathing passages of asthmatic patients.
The problem for asthmatics is that smoking weed is probably not all that good for their lungs. Studies have found that smoking marijuana can actually trigger an asthma attack. However the risk decreases significantly when cannabis is dry-herb vaporized, since offending plant particulates are minimized.
Does this mean it’s definitely safe? Well, as usual, the answer is that nobody really knows yet, and it’s going to take some time, again, before enough peer review has been done and any significant findings can be declared. So at the moment, smoking cannabis is a bit of a gamble—but one with very favorable odds. However, if it still sounds too risky, dry herb and concentrate vaporizing are still completely viable options. And don’t forget edibles!